MDB · PEAD ↓ 100

MongoDB reported Q2 FY2027 EPS of $0.54 on 2026-09-01, beating the $0.08 consensus by $0.46 (+575%) — yet the print-day tape told a different story entirely.

Print-day reaction was −4.2% versus the prior close of $453.37, an immediate sell-the-news move despite the dramatic EPS beat. The overnight gap from the T+0 close of $434.21 to the T+1 open of $379.25 extended the damage by a further −12.7%, signalling aggressive after-hours and pre-market liquidation with no stabilisation. Over the following two trading days the stock drifted an additional −1.8%, confirming no mean-reversion bid through T+3. Cumulative abnormal return of −19.1% versus SPY.US places this firmly in PEAD short territory; drift reinforces rather than reverses the initial reaction, and the read holds through 2026-11-27.